The American Heart Association (AHA) has estimated that over 350,000 individuals in the United States experience a sudden cardiac arrest (SCA) each year, which is a sudden, abrupt loss of heart function resulting in sudden cardiac death within minutes of onset. Unfortunately, 95 percent of SCA victims die because cardiopulmonary resuscitation (CPR) isn't provided soon enough.
CPR is the abbreviation for cardio pulmonary resuscitation, and is an emergency technique applied by combining artificial respiration and massage outside the heart, when breathing stops and the heart stops beating. Due to brain damage is likely to occur in just 4 to 6 minutes without oxygen supplying, and irreparable brain damage will be further caused while there is no oxygen supplying in more than 6 minutes. Accordingly, if the CPR is provided promptly, the breathing and circulation can be maintained to provide oxygen and blood flow to the brain so as to sustain life of patient in time. In another words, any cause of breath cease and cardiac arrest, including drowning, heart attack, car accident, electric shock, drug poisoning, gas poisoning and airway obstruction, before getting proper medical care, CPR is a effective choice to keep the brain cell and other organs from being damaged. With the merits of CPR described above, right now, the AHA trains more than 9 million people a year and it is determined to more than double that number, to 20 million, within the next five years.
However, manual CPR, even operated properly, will not provide enough efficiency to maintain the normal circulation of blood flowing to brain or heart due to, during processing CPR, the effectiveness getting decreased in occasions such as inadequate chest compression, rescuer fatigue, and moving patient by rescuer. Therefore, it has been a vital topic for the one skilled in this field to spend efforts providing an apparatus of cardiopulmonary resuscitator for overcoming the drawbacks of manual CPR.
Conventional technique for solve the above problem of manual CPR, such as U.S. Pat. No 6,171,267 applied by Michigan Instruments, Inc. in 1999, discloses a high impulse cardiopulmonary resuscitator shown in FIG. 1. The cardiopulmonary resuscitation method and apparatus that is adapted to performing high-impulse CPR includes providing a chamber having an expandable volume and a patient-contacting pad that moves as a function of volume of the chamber and supplying a controlled quantity of a fluid to the chamber. This results in increasing the chamber volume by a controlled amount, thereby compressing the patient's chest with the patient-contacting pad during a systolic phase.
Please refer to FIG. 1, the apparatus comprises a base 11, a column 12 supported by the base 11, and a cardiopulmonary resuscitation arm assembly 13 adjustably supported along the column 12. The cardiopulmonary resuscitation arm assembly 13 has a fluid control system additionally including a timing circuit, a control valve assembly and a pressure regulator. A flexible pressure hose 14 interconnects the portion of the pneumatic source providing pneumatic power. The timing circuit is selectively to operate to control valve assembly so as to control operating frequency and pressing depth of a massage pad 15.
Another conventional way, such as U.S. Pat. No 6,398,745 of Revivant Corporation, discloses a modular CPR assist device shown in FIG. 2A and FIG. 2B. The device includes a panel 20, a motor box 21 and a drive spool 22 driven by the motor box 21, a belt 23 and a computer module 24. The computer module 24 is programmed and operated to repeatedly turn the motor and release the clutch inside the motor box 21 to roll the compression belt 23 onto the drive spool 22 and release the drive spool 22 to allow the belt 23 to unroll so as to generate massage effect to the patient. The merits of the device can avoid causing injury to the chest during the operation and improve the efficiency of the compression.